The research objectives of this project are: (1) to compare the performances of patients with brain disease with those of normal subjects and patients in other diagnostic categories on perceptual, cognitive, psychomotor and language tasks with the aim of defining the distinctive performance characteristics of patients with brain disease; (2) to make within-group comparisons of patients with focal brain lesions to determine the relationship betwen various performance characteristics and locus of lesion; (3) to identify the basic disabilities underlying the defective performances of patients with brain disease on perceptual, cognitive, psychomotor and language tasks; (4) to develop standardized objective procedures for the assessment of behavioral disabilities in brain-diseased patients for clinical and investigative use.